Java tutorial
// Copyright 2014 The Bazel Authors. All rights reserved. // // Licensed under the Apache License, Version 2.0 (the "License"); // you may not use this file except in compliance with the License. // You may obtain a copy of the License at // // http://www.apache.org/licenses/LICENSE-2.0 // // Unless required by applicable law or agreed to in writing, software // distributed under the License is distributed on an "AS IS" BASIS, // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. // See the License for the specific language governing permissions and // limitations under the License. package com.google.devtools.build.xcode.xcodegen; import com.google.common.base.Optional; import com.google.common.base.Preconditions; import com.google.common.collect.ImmutableList; import com.google.common.collect.ImmutableSet; import com.google.common.collect.SetMultimap; import com.google.devtools.build.xcode.util.Mapping; import com.facebook.buck.apple.xcode.xcodeproj.PBXBuildFile; import com.facebook.buck.apple.xcode.xcodeproj.PBXFileReference; import com.facebook.buck.apple.xcode.xcodeproj.PBXReference; import com.facebook.buck.apple.xcode.xcodeproj.PBXReference.SourceTree; import com.facebook.buck.apple.xcode.xcodeproj.PBXVariantGroup; import com.facebook.buck.apple.xcode.xcodeproj.XCVersionGroup; import java.nio.file.Path; import java.util.ArrayList; import java.util.Collection; import java.util.HashMap; import java.util.List; import java.util.Map; /** * A kind of cache which makes it easier to collect and manage PBXBuildFile and PBXReference * objects. It knows how to create new PBXBuildFile, PBXVariantGroup, and PBXFileReference objects * from {@link Path} objects and sequences thereof. * <p> * A PBXFileReference specifies a path to a file and its <em>name</em>. The name is confusingly * defined as the real file name for non-localized files (e.g. "foo" in "bar/foo"), and the language * name for localized files (e.g. "en" in "bar/en.lproj/foo"). * <p> * A PBXVariantGroup is a set of PBXFileReferences with the same file name (the virtual name). Each * file is in some directory named *.lproj. For instance, the following files would belong to the * same PBXVariantGroup: * * <ul> * <li>foo1/en.lproj/file.strings * <li>foo2/ru.lproj/file.strings * </ul> * * Where the virtual name is "file.strings". Note that because of the way PBXVariantGroups are named * and specified in .xcodeproj files, it is possible Xcode does or will use it for groups not * defined by localization, but we currently ignore that possibility. * <p> * A PBXBuildFile is the simplest object - it is simply a reference to a PBXReference, which can be * either a PBXFileReference or PBXVariantGroup. The fact that PBXFileReference and PBXVariantGroup * are considered kinds of PBXReference is reflected in the Java inheritance hierarchy for the * classes that model these Xcode objects. * <p> * The PBXBuildFile is the object referred to in the build phases of targets, so it is seen as a * buildable or compilable unit. The PBXFileReference and PBXVariantGroup objects are referred to * by the PBXGroups, which define what is visible in the Project Navigator view in Xcode. * <p> * This class assumes that all paths given through the public API are specified relative to the * Xcodegen root, and creates PBXFileReferences that should be added to a group whose path is the * root. * TODO(bazel-team): Make this an immutable type, of which multiple instances are created as new * references and build files are added. The current API is side-effect-based and confusing. */ final class PBXBuildFiles implements HasProjectNavigatorFiles { /** * Map from Paths to the PBXBuildFile that encompasses all and only those Paths. Because the * {@link PBXBuildFile}s in this map encompass multiple files, their * {@link PBXBuildFile#getFileRef()} value is a {@link PBXVariantGroup} or {@link XCVersionGroup}. * <p> * Note that this Map reflects the intention of the API, namely that {"a"} does not map to the * same thing as {"a", "b"}, and you cannot get a build file with only one of the corresponding * files - you need the whole set. */ private Map<ImmutableSet<Path>, PBXBuildFile> aggregateBuildFiles; private Map<FileReference, PBXBuildFile> standaloneBuildFiles; private PBXFileReferences pbxReferences; private List<PBXReference> mainGroupReferences; public PBXBuildFiles(PBXFileReferences pbxFileReferences) { this.aggregateBuildFiles = new HashMap<>(); this.standaloneBuildFiles = new HashMap<>(); this.pbxReferences = Preconditions.checkNotNull(pbxFileReferences); this.mainGroupReferences = new ArrayList<>(); } private PBXBuildFile aggregateBuildFile(ImmutableSet<Path> paths, PBXReference reference) { Preconditions.checkArgument(!paths.isEmpty(), "paths must be non-empty"); for (PBXBuildFile cached : Mapping.of(aggregateBuildFiles, paths).asSet()) { return cached; } PBXBuildFile buildFile = new PBXBuildFile(reference); mainGroupReferences.add(reference); aggregateBuildFiles.put(paths, buildFile); return buildFile; } /** * Returns new or cached instances of PBXBuildFiles corresponding to files that may or may not * belong to an aggregate reference (see {@link AggregateReferenceType}). Files specified by the * {@code paths} argument are grouped into individual PBXBuildFiles using the given * {@link AggregateReferenceType}. Files that are standalone are not put in an aggregate * reference, but are put in a standalone PBXBuildFile in the returned sequence. */ public Iterable<PBXBuildFile> get(AggregateReferenceType type, Iterable<Path> paths) { ImmutableList.Builder<PBXBuildFile> result = new ImmutableList.Builder<>(); SetMultimap<AggregateKey, Path> keyedPaths = type.aggregates(paths); for (Map.Entry<AggregateKey, Collection<Path>> aggregation : keyedPaths.asMap().entrySet()) { if (!aggregation.getKey().isStandalone()) { ImmutableSet<Path> itemPaths = ImmutableSet.copyOf(aggregation.getValue()); result.add(aggregateBuildFile(itemPaths, type.create(aggregation.getKey(), fileReferences(itemPaths)))); } } for (Path generalResource : keyedPaths.get(AggregateKey.standalone())) { result.add(getStandalone(FileReference.of(generalResource.toString(), SourceTree.GROUP))); } return result.build(); } /** * Returns a new or cached instance of a PBXBuildFile for a file that is not part of a variant * group. */ public PBXBuildFile getStandalone(FileReference file) { for (PBXBuildFile cached : Mapping.of(standaloneBuildFiles, file).asSet()) { return cached; } PBXBuildFile buildFile = new PBXBuildFile(pbxReferences.get(file)); mainGroupReferences.add(pbxReferences.get(file)); standaloneBuildFiles.put(file, buildFile); return buildFile; } /** * Applies {@link #fileReference(Path)} to each item in the sequence. */ private final Iterable<PBXFileReference> fileReferences(Iterable<Path> paths) { ImmutableList.Builder<PBXFileReference> result = new ImmutableList.Builder<>(); for (Path path : paths) { result.add(fileReference(path)); } return result.build(); } /** * Returns a new or cached PBXFileReference for the given file. The name of the reference depends * on whether the file is in a localized (*.lproj) directory. If it is localized, then the name * of the reference is the name of the language (the text before ".lproj"). Otherwise, the name is * the same as the file name (e.g. Localizable.strings). This is confusing, but it is how Xcode * creates PBXFileReferences. */ private PBXFileReference fileReference(Path path) { Optional<String> language = Resources.languageOfLprojDir(path); String name = language.isPresent() ? language.get() : path.getFileName().toString(); return pbxReferences.get(FileReference.of(name, path.toString(), SourceTree.GROUP)); } @Override public Iterable<PBXReference> mainGroupReferences() { return mainGroupReferences; } }